1 /* Small compiler - Recursive descend expresion parser
3 * Copyright (c) ITB CompuPhase, 1997-2003
5 * This software is provided "as-is", without any express or implied warranty.
6 * In no event will the authors be held liable for any damages arising from
7 * the use of this software.
9 * Permission is granted to anyone to use this software for any purpose,
10 * including commercial applications, and to alter it and redistribute it
11 * freely, subject to the following restrictions:
13 * 1. The origin of this software must not be misrepresented; you must not
14 * claim that you wrote the original software. If you use this software in
15 * a product, an acknowledgment in the product documentation would be
16 * appreciated but is not required.
17 * 2. Altered source versions must be plainly marked as such, and must not be
18 * misrepresented as being the original software.
19 * 3. This notice may not be removed or altered from any source distribution.
31 #include <limits.h> /* for PATH_MAX */
34 #include "embryo_cc_sc.h"
36 static int skim(int *opstr, void (*testfunc) (int), int dropval,
37 int endval, int (*hier) (value *), value * lval);
38 static void dropout(int lvalue, void (*testfunc) (int val), int exit1,
40 static int plnge(int *opstr, int opoff, int (*hier) (value * lval),
41 value * lval, char *forcetag, int chkbitwise);
42 static int plnge1(int (*hier) (value * lval), value * lval);
43 static void plnge2(void (*oper) (void),
44 int (*hier) (value * lval),
45 value * lval1, value * lval2);
46 static cell calc(cell left, void (*oper) (), cell right,
48 static int hier13(value * lval);
49 static int hier12(value * lval);
50 static int hier11(value * lval);
51 static int hier10(value * lval);
52 static int hier9(value * lval);
53 static int hier8(value * lval);
54 static int hier7(value * lval);
55 static int hier6(value * lval);
56 static int hier5(value * lval);
57 static int hier4(value * lval);
58 static int hier3(value * lval);
59 static int hier2(value * lval);
60 static int hier1(value * lval1);
61 static int primary(value * lval);
62 static void clear_value(value * lval);
63 static void callfunction(symbol * sym);
64 static int dbltest(void (*oper) (), value * lval1, value * lval2);
65 static int commutative(void (*oper) ());
66 static int constant(value * lval);
68 static char lastsymbol[sNAMEMAX + 1]; /* name of last function/variable */
69 static int bitwise_opercount; /* count of bitwise operators in an expression */
71 /* Function addresses of binary operators for signed operations */
72 static void (*op1[17]) (void) =
74 os_mult, os_div, os_mod, /* hier3, index 0 */
75 ob_add, ob_sub, /* hier4, index 3 */
76 ob_sal, os_sar, ou_sar, /* hier5, index 5 */
77 ob_and, /* hier6, index 8 */
78 ob_xor, /* hier7, index 9 */
79 ob_or, /* hier8, index 10 */
80 os_le, os_ge, os_lt, os_gt, /* hier9, index 11 */
81 ob_eq, ob_ne, /* hier10, index 15 */
83 /* These two functions are defined because the functions inc() and dec() in
84 * SC4.C have a different prototype than the other code generation functions.
85 * The arrays for user-defined functions use the function pointers for
86 * identifying what kind of operation is requested; these functions must all
87 * have the same prototype. As inc() and dec() are special cases already, it
88 * is simplest to add two "do-nothing" functions.
100 * Searches for a binary operator a list of operators. The list is stored in
101 * the array "list". The last entry in the list should be set to 0.
103 * The index of an operator in "list" (if found) is returned in "opidx". If
104 * no operator is found, nextop() returns 0.
107 nextop(int *opidx, int *list)
112 if (matchtoken(*list))
114 return TRUE; /* found! */
122 return FALSE; /* entire list scanned, nothing found */
126 check_userop(void (*oper) (void), int tag1, int tag2, int numparam,
127 value * lval, int *resulttag)
129 static char *binoperstr[] = { "*", "/", "%", "+", "-", "", "", "",
130 "", "", "", "<=", ">=", "<", ">", "==", "!="
132 static int binoper_savepri[] =
133 { FALSE, FALSE, FALSE, FALSE, FALSE, FALSE,
134 FALSE, FALSE, FALSE, FALSE, FALSE,
135 TRUE, TRUE, TRUE, TRUE, FALSE, FALSE
137 static char *unoperstr[] = { "!", "-", "++", "--" };
138 static void (*unopers[]) (void) =
140 lneg, neg, user_inc, user_dec};
141 char opername[4] = "", symbolname[sNAMEMAX + 1];
142 int i, swapparams, savepri, savealt;
146 /* since user-defined operators on untagged operands are forbidden, we have
149 assert(numparam == 1 || numparam == 2);
150 if (tag1 == 0 && (numparam == 1 || tag2 == 0))
153 savepri = savealt = FALSE;
154 /* find the name with the operator */
159 /* assignment operator: a special case */
160 strcpy(opername, "=");
162 && (lval->ident == iARRAYCELL || lval->ident == iARRAYCHAR))
167 assert((sizeof binoperstr / sizeof binoperstr[0]) ==
168 (sizeof op1 / sizeof op1[0]));
169 for (i = 0; i < sizeof op1 / sizeof op1[0]; i++)
173 strcpy(opername, binoperstr[i]);
174 savepri = binoper_savepri[i];
182 assert(oper != NULL);
183 assert(numparam == 1);
184 /* try a select group of unary operators */
185 assert((sizeof unoperstr / sizeof unoperstr[0]) ==
186 (sizeof unopers / sizeof unopers[0]));
187 if (opername[0] == '\0')
189 for (i = 0; i < sizeof unopers / sizeof unopers[0]; i++)
191 if (oper == unopers[i])
193 strcpy(opername, unoperstr[i]);
199 /* if not found, quit */
200 if (opername[0] == '\0')
203 /* create a symbol name from the tags and the operator name */
204 assert(numparam == 1 || numparam == 2);
205 operator_symname(symbolname, opername, tag1, tag2, numparam, tag2);
207 sym = findglb(symbolname);
208 if (sym == NULL /*|| (sym->usage & uDEFINE)==0 */ )
209 { /* ??? should not check uDEFINE; first pass clears these bits */
210 /* check for commutative operators */
211 if (tag1 == tag2 || oper == NULL || !commutative(oper))
212 return FALSE; /* not commutative, cannot swap operands */
213 /* if arrived here, the operator is commutative and the tags are different,
214 * swap tags and try again
216 assert(numparam == 2); /* commutative operator must be a binary operator */
217 operator_symname(symbolname, opername, tag2, tag1, numparam, tag1);
219 sym = findglb(symbolname);
220 if (sym == NULL /*|| (sym->usage & uDEFINE)==0 */ )
224 /* check existance and the proper declaration of this function */
225 if ((sym->usage & uMISSING) != 0 || (sym->usage & uPROTOTYPED) == 0)
227 char symname[2 * sNAMEMAX + 16]; /* allow space for user defined operators */
229 funcdisplayname(symname, sym->name);
230 if ((sym->usage & uMISSING) != 0)
231 error(4, symname); /* function not defined */
232 if ((sym->usage & uPROTOTYPED) == 0)
233 error(71, symname); /* operator must be declared before use */
236 /* we don't want to use the redefined operator in the function that
237 * redefines the operator itself, otherwise the snippet below gives
238 * an unexpected recursion:
239 * fixed:operator+(fixed:a, fixed:b)
245 /* for increment and decrement operators, the symbol must first be loaded
246 * (and stored back afterwards)
248 if (oper == user_inc || oper == user_dec)
251 assert(lval != NULL);
252 if (lval->ident == iARRAYCELL || lval->ident == iARRAYCHAR)
253 push1(); /* save current address in PRI */
254 rvalue(lval); /* get the symbol's value in PRI */
257 assert(!savepri || !savealt); /* either one MAY be set, but not both */
260 /* the chained comparison operators require that the ALT register is
261 * unmodified, so we save it here; actually, we save PRI because the normal
262 * instruction sequence (without user operator) swaps PRI and ALT
264 push1(); /* right-hand operand is in PRI */
268 /* for the assignment operator, ALT may contain an address at which the
269 * result must be stored; this address must be preserved accross the
272 assert(lval != NULL); /* this was checked earlier */
273 assert(lval->ident == iARRAYCELL || lval->ident == iARRAYCHAR); /* checked earlier */
277 /* push parameters, call the function */
278 paramspassed = (oper == NULL) ? 1 : numparam;
279 switch (paramspassed)
285 /* note that 1) a function expects that the parameters are pushed
286 * in reversed order, and 2) the left operand is in the secondary register
287 * and the right operand is in the primary register */
302 endexpr(FALSE); /* mark the end of a sub-expression */
303 pushval((cell) paramspassed * sizeof(cell));
304 assert(sym->ident == iFUNCTN);
305 ffcall(sym, paramspassed);
306 if (sc_status != statSKIP)
307 markusage(sym, uREAD); /* do not mark as "used" when this call itself is skipped */
308 if (sym->x.lib != NULL)
309 sym->x.lib->value += 1; /* increment "usage count" of the library */
310 sideeffect = TRUE; /* assume functions carry out a side-effect */
311 assert(resulttag != NULL);
312 *resulttag = sym->tag; /* save tag of the called function */
314 if (savepri || savealt)
315 pop2(); /* restore the saved PRI/ALT that into ALT */
316 if (oper == user_inc || oper == user_dec)
318 assert(lval != NULL);
319 if (lval->ident == iARRAYCELL || lval->ident == iARRAYCHAR)
320 pop2(); /* restore address (in ALT) */
321 store(lval); /* store PRI in the symbol */
322 moveto1(); /* make sure PRI is restored on exit */
328 matchtag(int formaltag, int actualtag, int allowcoerce)
330 if (formaltag != actualtag)
332 /* if the formal tag is zero and the actual tag is not "fixed", the actual
333 * tag is "coerced" to zero
335 if (!allowcoerce || formaltag != 0 || (actualtag & FIXEDTAG) != 0)
342 * The AMX pseudo-processor has no direct support for logical (boolean)
343 * operations. These have to be done via comparing and jumping. Since we are
344 * already jumping through the code, we might as well implement an "early
345 * drop-out" evaluation (also called "short-circuit"). This conforms to
348 * expr1 || expr2 expr2 will only be evaluated if expr1 is false.
349 * expr1 && expr2 expr2 will only be evaluated if expr1 is true.
351 * expr1 || expr2 && expr3 expr2 will only be evaluated if expr1 is false
352 * and expr3 will only be evaluated if expr1 is
353 * false and expr2 is true.
355 * Code generation for the last example proceeds thus:
359 * jump to "l1" if result of expr1 not equal to 0
361 * -> operator && found; skip to higher level in hierarchy diagram
362 * jump to "l2" if result of expr2 equal to 0
364 * jump to "l2" if result of expr3 equal to 0
365 * set expression result to 1 (true)
367 * l2: set expression result to 0 (false)
369 * <- drop back to previous hierarchy level
370 * jump to "l1" if result of expr2 && expr3 not equal to 0
371 * set expression result to 0 (false)
373 * l1: set expression result to 1 (true)
378 /* Skim over terms adjoining || and && operators
379 * dropval The value of the expression after "dropping out". An "or" drops
380 * out when the left hand is TRUE, so dropval must be 1 on "or"
382 * endval The value of the expression when no expression drops out. In an
383 * "or" expression, this happens when both the left hand and the
384 * right hand are FALSE, so endval must be 0 for "or" expressions.
387 skim(int *opstr, void (*testfunc) (int), int dropval, int endval,
388 int (*hier) (value *), value * lval)
390 int lvalue, hits, droplab, endlab, opidx;
396 stgget(&index, &cidx); /* mark position in code generator */
397 hits = FALSE; /* no logical operators "hit" yet */
398 allconst = TRUE; /* assume all values "const" */
400 droplab = 0; /* to avoid a compiler warning */
403 lvalue = plnge1(hier, lval); /* evaluate left expression */
405 allconst = allconst && (lval->ident == iCONSTEXPR);
410 /* one operator was already found */
411 if (testfunc == jmp_ne0)
412 lval->constval = lval->constval || constval;
414 lval->constval = lval->constval && constval;
416 constval = lval->constval; /* save result accumulated so far */
419 if (nextop(&opidx, opstr))
423 /* this is the first operator in the list */
425 droplab = getlabel();
427 dropout(lvalue, testfunc, droplab, lval);
430 { /* no (more) identical operators */
431 dropout(lvalue, testfunc, droplab, lval); /* found at least one operator! */
433 jumplabel(endlab = getlabel());
441 lval->ident = iCONSTEXPR;
442 lval->constval = constval;
443 stgdel(index, cidx); /* scratch generated code and calculate */
447 lval->ident = iEXPRESSION;
454 return lvalue; /* none of the operators in "opstr" were found */
461 * Reads into the primary register the variable pointed to by lval if
462 * plunging through the hierarchy levels detected an lvalue. Otherwise
463 * if a constant was detected, it is loaded. If there is no constant and
464 * no lvalue, the primary register must already contain the expression
467 * After that, the compare routines "jmp_ne0" or "jmp_eq0" are called, which
468 * compare the primary register against 0, and jump to the "early drop-out"
469 * label "exit1" if the condition is true.
472 dropout(int lvalue, void (*testfunc) (int val), int exit1, value * lval)
476 else if (lval->ident == iCONSTEXPR)
477 const1(lval->constval);
482 checkfunction(value * lval)
484 symbol *sym = lval->sym;
486 if (sym == NULL || (sym->ident != iFUNCTN && sym->ident != iREFFUNC))
487 return; /* no known symbol, or not a function result */
489 if ((sym->usage & uDEFINE) != 0)
491 /* function is defined, can now check the return value (but make an
492 * exception for directly recursive functions)
494 if (sym != curfunc && (sym->usage & uRETVALUE) == 0)
496 char symname[2 * sNAMEMAX + 16]; /* allow space for user defined operators */
498 funcdisplayname(symname, sym->name);
499 error(209, symname); /* function should return a value */
504 /* function not yet defined, set */
505 sym->usage |= uRETVALUE; /* make sure that a future implementation of
506 * the function uses "return <value>" */
511 * Plunge to a lower level
514 plnge(int *opstr, int opoff, int (*hier) (value * lval), value * lval,
515 char *forcetag, int chkbitwise)
519 value lval2 = { NULL, 0, 0, 0, 0, NULL };
521 lvalue = plnge1(hier, lval);
522 if (nextop(&opidx, opstr) == 0)
523 return lvalue; /* no operator in "opstr" found */
529 if (chkbitwise && count++ > 0 && bitwise_opercount != 0)
531 opidx += opoff; /* add offset to index returned by nextop() */
532 plnge2(op1[opidx], hier, lval, &lval2);
533 if (op1[opidx] == ob_and || op1[opidx] == ob_or)
535 if (forcetag != NULL)
536 lval->tag = sc_addtag(forcetag);
538 while (nextop(&opidx, opstr)); /* do */
539 return FALSE; /* result of expression is not an lvalue */
544 * Binary plunge to lower level; this is very simular to plnge, but
545 * it has special code generation sequences for chained operations.
548 plnge_rel(int *opstr, int opoff, int (*hier) (value * lval), value * lval)
551 value lval2 = { NULL, 0, 0, 0, 0, NULL };
554 /* this function should only be called for relational operators */
555 assert(op1[opoff] == os_le);
556 lvalue = plnge1(hier, lval);
557 if (nextop(&opidx, opstr) == 0)
558 return lvalue; /* no operator in "opstr" found */
562 lval->boolresult = TRUE;
565 /* same check as in plnge(), but "chkbitwise" is always TRUE */
566 if (count > 0 && bitwise_opercount != 0)
571 *lval = lval2; /* copy right hand expression of the previous iteration */
574 plnge2(op1[opidx], hier, lval, &lval2);
578 while (nextop(&opidx, opstr)); /* enddo */
579 lval->constval = lval->boolresult;
580 lval->tag = sc_addtag("bool"); /* force tag to be "bool" */
581 return FALSE; /* result of expression is not an lvalue */
586 * Unary plunge to lower level
587 * Called by: skim(), plnge(), plnge2(), plnge_rel(), hier14() and hier13()
590 plnge1(int (*hier) (value * lval), value * lval)
595 stgget(&index, &cidx); /* mark position in code generator */
596 lvalue = (*hier) (lval);
597 if (lval->ident == iCONSTEXPR)
598 stgdel(index, cidx); /* load constant later */
604 * Binary plunge to lower level
605 * Called by: plnge(), plnge_rel(), hier14() and hier1()
608 plnge2(void (*oper) (void),
609 int (*hier) (value * lval), value * lval1, value * lval2)
614 stgget(&index, &cidx); /* mark position in code generator */
615 if (lval1->ident == iCONSTEXPR)
616 { /* constant on left side; it is not yet loaded */
617 if (plnge1(hier, lval2))
618 rvalue(lval2); /* load lvalue now */
619 else if (lval2->ident == iCONSTEXPR)
620 const1(lval2->constval << dbltest(oper, lval2, lval1));
621 const2(lval1->constval << dbltest(oper, lval2, lval1));
622 /* ^ doubling of constants operating on integer addresses */
623 /* is restricted to "add" and "subtract" operators */
626 { /* non-constant on left side */
628 if (plnge1(hier, lval2))
630 if (lval2->ident == iCONSTEXPR)
631 { /* constant on right side */
632 if (commutative(oper))
633 { /* test for commutative operators */
634 value lvaltmp = { NULL, 0, 0, 0, 0, NULL };
635 stgdel(index, cidx); /* scratch push1() and constant fetch (then
636 * fetch the constant again */
637 const2(lval2->constval << dbltest(oper, lval1, lval2));
638 /* now, the primary register has the left operand and the secondary
639 * register the right operand; swap the "lval" variables so that lval1
640 * is associated with the secondary register and lval2 with the
641 * primary register, as is the "normal" case.
649 const1(lval2->constval << dbltest(oper, lval1, lval2));
650 pop2(); /* pop result of left operand into secondary register */
654 { /* non-constants on both sides */
656 if (dbltest(oper, lval1, lval2))
657 cell2addr(); /* double primary register */
658 if (dbltest(oper, lval2, lval1))
659 cell2addr_alt(); /* double secondary register */
664 /* If used in an expression, a function should return a value.
665 * If the function has been defined, we can check this. If the
666 * function was not defined, we can set this requirement (so that
667 * a future function definition can check this bit.
669 checkfunction(lval1);
670 checkfunction(lval2);
671 if (lval1->ident == iARRAY || lval1->ident == iREFARRAY)
674 (lval1->sym != NULL) ? lval1->sym->name : "-unknown-";
675 error(33, ptr); /* array must be indexed */
677 else if (lval2->ident == iARRAY || lval2->ident == iREFARRAY)
680 (lval2->sym != NULL) ? lval2->sym->name : "-unknown-";
681 error(33, ptr); /* array must be indexed */
683 /* ??? ^^^ should do same kind of error checking with functions */
685 /* check whether an "operator" function is defined for the tag names
686 * (a constant expression cannot be optimized in that case)
688 if (check_userop(oper, lval1->tag, lval2->tag, 2, NULL, &lval1->tag))
690 lval1->ident = iEXPRESSION;
693 else if (lval1->ident == iCONSTEXPR && lval2->ident == iCONSTEXPR)
695 /* only constant expression if both constant */
696 stgdel(index, cidx); /* scratch generated code and calculate */
697 if (!matchtag(lval1->tag, lval2->tag, FALSE))
698 error(213); /* tagname mismatch */
700 calc(lval1->constval, oper, lval2->constval,
705 if (!matchtag(lval1->tag, lval2->tag, FALSE))
706 error(213); /* tagname mismatch */
707 (*oper) (); /* do the (signed) operation */
708 lval1->ident = iEXPRESSION;
714 truemodulus(cell a, cell b)
716 return (a % b + b) % b;
720 calc(cell left, void (*oper) (), cell right, char *boolresult)
723 return (left | right);
724 else if (oper == ob_xor)
725 return (left ^ right);
726 else if (oper == ob_and)
727 return (left & right);
728 else if (oper == ob_eq)
729 return (left == right);
730 else if (oper == ob_ne)
731 return (left != right);
732 else if (oper == os_le)
733 return *boolresult &= (char)(left <= right), right;
734 else if (oper == os_ge)
735 return *boolresult &= (char)(left >= right), right;
736 else if (oper == os_lt)
737 return *boolresult &= (char)(left < right), right;
738 else if (oper == os_gt)
739 return *boolresult &= (char)(left > right), right;
740 else if (oper == os_sar)
741 return (left >> (int)right);
742 else if (oper == ou_sar)
743 return ((ucell) left >> (ucell) right);
744 else if (oper == ob_sal)
745 return ((ucell) left << (int)right);
746 else if (oper == ob_add)
747 return (left + right);
748 else if (oper == ob_sub)
749 return (left - right);
750 else if (oper == os_mult)
751 return (left * right);
752 else if (oper == os_div)
753 return (left - truemodulus(left, right)) / right;
754 else if (oper == os_mod)
755 return truemodulus(left, right);
757 error(29); /* invalid expression, assumed 0 (this should never occur) */
762 expression(int *constant, cell * val, int *tag, int chkfuncresult)
764 value lval = { NULL, 0, 0, 0, 0, NULL };
768 if (lval.ident == iCONSTEXPR)
769 { /* constant expression */
771 *val = lval.constval;
781 checkfunction(&lval);
786 array_totalsize(symbol * sym)
791 assert(sym->ident == iARRAY || sym->ident == iREFARRAY);
792 length = sym->dim.array.length;
793 if (sym->dim.array.level > 0)
795 cell sublength = array_totalsize(finddepend(sym));
798 length = length + length * sublength;
806 array_levelsize(symbol * sym, int level)
809 assert(sym->ident == iARRAY || sym->ident == iREFARRAY);
810 assert(level <= sym->dim.array.level);
813 sym = finddepend(sym);
816 return sym->dim.array.length;
821 * Lowest hierarchy level (except for the , operator).
823 * Global references: intest (reffered to only)
826 hier14(value * lval1)
829 value lval2 = { NULL, 0, 0, 0, 0, NULL };
830 value lval3 = { NULL, 0, 0, 0, 0, NULL };
836 cell arrayidx1[sDIMEN_MAX], arrayidx2[sDIMEN_MAX]; /* last used array indices */
839 bwcount = bitwise_opercount;
840 bitwise_opercount = 0;
841 for (i = 0; i < sDIMEN_MAX; i++)
842 arrayidx1[i] = arrayidx2[i] = 0;
843 org_arrayidx = lval1->arrayidx; /* save current pointer, to reset later */
844 if (lval1->arrayidx == NULL)
845 lval1->arrayidx = arrayidx1;
846 lvalue = plnge1(hier13, lval1);
847 if (lval1->ident != iARRAYCELL && lval1->ident != iARRAYCHAR)
848 lval1->arrayidx = NULL;
849 if (lval1->ident == iCONSTEXPR) /* load constant here */
850 const1(lval1->constval);
851 tok = lex(&val, &st);
887 case '=': /* simple assignment */
890 error(211); /* possibly unintended assignment */
894 bitwise_opercount = bwcount;
895 lval1->arrayidx = org_arrayidx; /* restore array index pointer */
899 /* if we get here, it was an assignment; first check a few special cases
900 * and then the general */
901 if (lval1->ident == iARRAYCHAR)
903 /* special case, assignment to packed character in a cell is permitted */
906 else if (lval1->ident == iARRAY || lval1->ident == iREFARRAY)
908 /* array assignment is permitted too (with restrictions) */
910 return error(23); /* array assignment must be simple assigment */
911 assert(lval1->sym != NULL);
912 if (array_totalsize(lval1->sym) == 0)
913 return error(46, lval1->sym->name); /* unknown array size */
917 /* operand on left side of assignment must be lvalue */
919 return error(22); /* must be lvalue */
920 /* may not change "constant" parameters */
921 assert(lval1->sym != NULL);
922 if ((lval1->sym->usage & uCONST) != 0)
923 return error(22); /* assignment to const argument */
924 lval3 = *lval1; /* save symbol to enable storage of expresion result */
925 lval1->arrayidx = org_arrayidx; /* restore array index pointer */
926 if (lval1->ident == iARRAYCELL || lval1->ident == iARRAYCHAR
927 || lval1->ident == iARRAY || lval1->ident == iREFARRAY)
929 /* if indirect fetch: save PRI (cell address) */
935 lval2.arrayidx = arrayidx2;
936 plnge2(oper, hier14, lval1, &lval2);
937 if (lval2.ident != iARRAYCELL && lval2.ident != iARRAYCHAR)
938 lval2.arrayidx = NULL;
941 if (!oper && lval3.arrayidx != NULL && lval2.arrayidx != NULL
942 && lval3.ident == lval2.ident && lval3.sym == lval2.sym)
946 assert(lval3.arrayidx == arrayidx1);
947 assert(lval2.arrayidx == arrayidx2);
948 for (i = 0; i < sDIMEN_MAX; i++)
949 same = same && (lval3.arrayidx[i] == lval2.arrayidx[i]);
951 error(226, lval3.sym->name); /* self-assignment */
959 plnge2(oper, hier14, lval1, &lval2);
963 /* if direct fetch and simple assignment: no "push"
964 * and "pop" needed -> call hier14() directly, */
966 rvalue(&lval2); /* instead of plnge2(). */
967 checkfunction(&lval2);
968 /* check whether lval2 and lval3 (old lval1) refer to the same variable */
969 if (lval2.ident == iVARIABLE && lval3.ident == lval2.ident
970 && lval3.sym == lval2.sym)
972 assert(lval3.sym != NULL);
973 error(226, lval3.sym->name); /* self-assignment */
977 if (lval3.ident == iARRAY || lval3.ident == iREFARRAY)
979 /* left operand is an array, right operand should be an array variable
980 * of the same size and the same dimension, an array literal (of the
981 * same size) or a literal string.
983 int exactmatch = TRUE;
985 if (lval2.ident != iARRAY && lval2.ident != iREFARRAY)
986 error(33, lval3.sym->name); /* array must be indexed */
987 if (lval2.sym != NULL)
989 val = lval2.sym->dim.array.length; /* array variable */
990 level = lval2.sym->dim.array.level;
994 val = lval2.constval; /* literal array */
996 /* If val is negative, it means that lval2 is a
997 * literal string. The string array size may be
998 * smaller than the destination array.
1006 if (lval3.sym->dim.array.level != level)
1007 return error(48); /* array dimensions must match */
1008 else if (lval3.sym->dim.array.length < val
1009 || (exactmatch && lval3.sym->dim.array.length > val))
1010 return error(47); /* array sizes must match */
1013 /* check the sizes of all sublevels too */
1014 symbol *sym1 = lval3.sym;
1015 symbol *sym2 = lval2.sym;
1018 assert(sym1 != NULL && sym2 != NULL);
1019 /* ^^^ sym2 must be valid, because only variables can be
1020 * multi-dimensional (there are no multi-dimensional arrays),
1021 * sym1 must be valid because it must be an lvalue
1024 for (i = 0; i < level; i++)
1026 sym1 = finddepend(sym1);
1027 sym2 = finddepend(sym2);
1028 assert(sym1 != NULL && sym2 != NULL);
1029 /* ^^^ both arrays have the same dimensions (this was checked
1030 * earlier) so the dependend should always be found
1032 if (sym1->dim.array.length != sym2->dim.array.length)
1033 error(47); /* array sizes must match */
1035 /* get the total size in cells of the multi-dimensional array */
1036 val = array_totalsize(lval3.sym);
1037 assert(val > 0); /* already checked */
1042 /* left operand is not an array, right operand should then not be either */
1043 if (lval2.ident == iARRAY || lval2.ident == iREFARRAY)
1044 error(6); /* must be assigned to an array */
1046 if (lval3.ident == iARRAY || lval3.ident == iREFARRAY)
1048 memcopy(val * sizeof(cell));
1052 check_userop(NULL, lval2.tag, lval3.tag, 2, &lval3, &lval2.tag);
1053 store(&lval3); /* now, store the expression result */
1055 if (!oper && !matchtag(lval3.tag, lval2.tag, TRUE))
1056 error(213); /* tagname mismatch (if "oper", warning already given in plunge2()) */
1058 markusage(lval3.sym, uWRITTEN);
1060 bitwise_opercount = bwcount;
1061 return FALSE; /* expression result is never an lvalue */
1065 hier13(value * lval)
1067 int lvalue, flab1, flab2;
1068 value lval2 = { NULL, 0, 0, 0, 0, NULL };
1071 lvalue = plnge1(hier12, lval);
1072 if (matchtoken('?'))
1080 else if (lval->ident == iCONSTEXPR)
1082 const1(lval->constval);
1083 error(lval->constval ? 206 : 205); /* redundant test */
1085 jmp_eq0(flab1); /* go to second expression if primary register==0 */
1093 array1 = (lval->ident == iARRAY || lval->ident == iREFARRAY);
1094 array2 = (lval2.ident == iARRAY || lval2.ident == iREFARRAY);
1095 if (array1 && !array2)
1098 (lval->sym->name != NULL) ? lval->sym->name : "-unknown-";
1099 error(33, ptr); /* array must be indexed */
1101 else if (!array1 && array2)
1104 (lval2.sym->name != NULL) ? lval2.sym->name : "-unknown-";
1105 error(33, ptr); /* array must be indexed */
1107 /* ??? if both are arrays, should check dimensions */
1108 if (!matchtag(lval->tag, lval2.tag, FALSE))
1109 error(213); /* tagname mismatch ('true' and 'false' expressions) */
1111 if (lval->ident == iARRAY)
1112 lval->ident = iREFARRAY; /* iARRAY becomes iREFARRAY */
1113 else if (lval->ident != iREFARRAY)
1114 lval->ident = iEXPRESSION; /* iREFARRAY stays iREFARRAY, rest becomes iEXPRESSION */
1115 return FALSE; /* conditional expression is no lvalue */
1123 /* the order of the operators in these lists is important and must cohere */
1124 /* with the order of the operators in the array "op1" */
1125 static int list3[] = { '*', '/', '%', 0 };
1126 static int list4[] = { '+', '-', 0 };
1127 static int list5[] = { tSHL, tSHR, tSHRU, 0 };
1128 static int list6[] = { '&', 0 };
1129 static int list7[] = { '^', 0 };
1130 static int list8[] = { '|', 0 };
1131 static int list9[] = { tlLE, tlGE, '<', '>', 0 };
1132 static int list10[] = { tlEQ, tlNE, 0 };
1133 static int list11[] = { tlAND, 0 };
1134 static int list12[] = { tlOR, 0 };
1137 hier12(value * lval)
1139 return skim(list12, jmp_ne0, 1, 0, hier11, lval);
1143 hier11(value * lval)
1145 return skim(list11, jmp_eq0, 0, 1, hier10, lval);
1149 hier10(value * lval)
1151 return plnge(list10, 15, hier9, lval, "bool", TRUE);
1152 } /* ^ this variable is the starting index in the op1[]
1153 * array of the operators of this hierarchy level */
1157 { /* <=, >=, <, > */
1158 return plnge_rel(list9, 11, hier8, lval);
1164 return plnge(list8, 10, hier7, lval, NULL, FALSE);
1170 return plnge(list7, 9, hier6, lval, NULL, FALSE);
1176 return plnge(list6, 8, hier5, lval, NULL, FALSE);
1182 return plnge(list5, 5, hier4, lval, NULL, FALSE);
1188 return plnge(list4, 3, hier3, lval, NULL, FALSE);
1194 return plnge(list3, 0, hier2, lval, NULL, FALSE);
1201 int tag, paranthese;
1207 tok = lex(&val, &st);
1210 case tINC: /* ++lval */
1212 return error(22); /* must be lvalue */
1213 assert(lval->sym != NULL);
1214 if ((lval->sym->usage & uCONST) != 0)
1215 return error(22); /* assignment to const argument */
1216 if (!check_userop(user_inc, lval->tag, 0, 1, lval, &lval->tag))
1217 inc(lval); /* increase variable first */
1218 rvalue(lval); /* and read the result into PRI */
1220 return FALSE; /* result is no longer lvalue */
1221 case tDEC: /* --lval */
1223 return error(22); /* must be lvalue */
1224 assert(lval->sym != NULL);
1225 if ((lval->sym->usage & uCONST) != 0)
1226 return error(22); /* assignment to const argument */
1227 if (!check_userop(user_dec, lval->tag, 0, 1, lval, &lval->tag))
1228 dec(lval); /* decrease variable first */
1229 rvalue(lval); /* and read the result into PRI */
1231 return FALSE; /* result is no longer lvalue */
1232 case '~': /* ~ (one's complement) */
1235 invert(); /* bitwise NOT */
1236 lval->constval = ~lval->constval;
1238 case '!': /* ! (logical negate) */
1241 if (check_userop(lneg, lval->tag, 0, 1, NULL, &lval->tag))
1243 lval->ident = iEXPRESSION;
1248 lneg(); /* 0 -> 1, !0 -> 0 */
1249 lval->constval = !lval->constval;
1250 lval->tag = sc_addtag("bool");
1253 case '-': /* unary - (two's complement) */
1256 /* make a special check for a constant expression with the tag of a
1257 * rational number, so that we can simple swap the sign of that constant.
1259 if (lval->ident == iCONSTEXPR && lval->tag == sc_rationaltag
1260 && sc_rationaltag != 0)
1262 if (rational_digits == 0)
1264 float *f = (float *)&lval->constval;
1266 *f = -*f; /* this modifies lval->constval */
1270 /* the negation of a fixed point number is just an integer negation */
1271 lval->constval = -lval->constval;
1274 else if (check_userop(neg, lval->tag, 0, 1, NULL, &lval->tag))
1276 lval->ident = iEXPRESSION;
1281 neg(); /* arithmic negation */
1282 lval->constval = -lval->constval;
1285 case tLABEL: /* tagname override */
1286 tag = sc_addtag(st);
1287 lvalue = hier2(lval);
1292 while (matchtoken('('))
1294 tok = lex(&val, &st);
1296 return error(20, st); /* illegal symbol name */
1300 if (sym != NULL && sym->ident != iFUNCTN && sym->ident != iREFFUNC
1301 && (sym->usage & uDEFINE) == 0)
1302 sym = NULL; /* symbol is not a function, it is in the table, but not "defined" */
1303 val = (sym != NULL);
1304 if (!val && find_subst(st, strlen(st)) != NULL)
1307 lval->ident = iCONSTEXPR;
1308 lval->constval = val;
1309 const1(lval->constval);
1310 while (paranthese--)
1315 while (matchtoken('('))
1317 tok = lex(&val, &st);
1319 return error(20, st); /* illegal symbol name */
1324 return error(17, st); /* undefined symbol */
1325 if (sym->ident == iCONSTEXPR)
1326 error(39); /* constant symbol has no size */
1327 else if (sym->ident == iFUNCTN || sym->ident == iREFFUNC)
1328 error(72); /* "function" symbol has no size */
1329 else if ((sym->usage & uDEFINE) == 0)
1330 return error(17, st); /* undefined symbol (symbol is in the table, but it is "used" only) */
1332 lval->ident = iCONSTEXPR;
1333 lval->constval = 1; /* preset */
1334 if (sym->ident == iARRAY || sym->ident == iREFARRAY)
1338 for (level = 0; matchtoken('['); level++)
1340 if (level > sym->dim.array.level)
1341 error(28); /* invalid subscript */
1343 lval->constval = array_levelsize(sym, level);
1344 if (lval->constval == 0 && strchr(lptr, PREPROC_TERM) == NULL)
1345 error(224, st); /* indeterminate array size in "sizeof" expression */
1347 const1(lval->constval);
1348 while (paranthese--)
1353 while (matchtoken('('))
1355 tok = lex(&val, &st);
1356 if (tok != tSYMBOL && tok != tLABEL)
1357 return error(20, st); /* illegal symbol name */
1360 tag = sc_addtag(st);
1368 return error(17, st); /* undefined symbol */
1369 if ((sym->usage & uDEFINE) == 0)
1370 return error(17, st); /* undefined symbol (symbol is in the table, but it is "used" only) */
1375 lval->ident = iCONSTEXPR;
1376 lval->constval = tag;
1377 const1(lval->constval);
1378 while (paranthese--)
1383 lvalue = hier1(lval);
1384 /* check for postfix operators */
1385 if (matchtoken(';'))
1387 /* Found a ';', do not look further for postfix operators */
1388 lexpush(); /* push ';' back after successful match */
1391 else if (matchtoken(tTERM))
1393 /* Found a newline that ends a statement (this is the case when
1394 * semicolons are optional). Note that an explicit semicolon was
1395 * handled above. This case is similar, except that the token must
1396 * not be pushed back.
1402 tok = lex(&val, &st);
1405 case tINC: /* lval++ */
1407 return error(22); /* must be lvalue */
1408 assert(lval->sym != NULL);
1409 if ((lval->sym->usage & uCONST) != 0)
1410 return error(22); /* assignment to const argument */
1411 /* on incrementing array cells, the address in PRI must be saved for
1412 * incremening the value, whereas the current value must be in PRI
1415 saveresult = (lval->ident == iARRAYCELL
1416 || lval->ident == iARRAYCHAR);
1418 push1(); /* save address in PRI */
1419 rvalue(lval); /* read current value into PRI */
1421 swap1(); /* save PRI on the stack, restore address in PRI */
1423 (user_inc, lval->tag, 0, 1, lval, &lval->tag))
1424 inc(lval); /* increase variable afterwards */
1426 pop1(); /* restore PRI (result of rvalue()) */
1428 return FALSE; /* result is no longer lvalue */
1429 case tDEC: /* lval-- */
1431 return error(22); /* must be lvalue */
1432 assert(lval->sym != NULL);
1433 if ((lval->sym->usage & uCONST) != 0)
1434 return error(22); /* assignment to const argument */
1435 saveresult = (lval->ident == iARRAYCELL
1436 || lval->ident == iARRAYCHAR);
1438 push1(); /* save address in PRI */
1439 rvalue(lval); /* read current value into PRI */
1441 swap1(); /* save PRI on the stack, restore address in PRI */
1443 (user_dec, lval->tag, 0, 1, lval, &lval->tag))
1444 dec(lval); /* decrease variable afterwards */
1446 pop1(); /* restore PRI (result of rvalue()) */
1449 case tCHAR: /* char (compute required # of cells */
1450 if (lval->ident == iCONSTEXPR)
1452 lval->constval *= charbits / 8; /* from char to bytes */
1454 (lval->constval + sizeof(cell) - 1) / sizeof(cell);
1459 rvalue(lval); /* fetch value if not already in PRI */
1460 char2addr(); /* from characters to bytes */
1461 addconst(sizeof(cell) - 1); /* make sure the value is rounded up */
1462 addr2cell(); /* truncate to number of cells */
1475 * The highest hierarchy level: it looks for pointer and array indices
1476 * and function calls.
1477 * Generates code to fetch a pointer value if it is indexed and code to
1478 * add to the pointer value or the array address (the address is already
1479 * read at primary()). It also generates code to fetch a function address
1480 * if that hasn't already been done at primary() (check lval[4]) and calls
1481 * callfunction() to call the function.
1484 hier1(value * lval1)
1486 int lvalue, index, tok, symtok;
1488 value lval2 = { NULL, 0, 0, 0, 0, NULL };
1493 lvalue = primary(lval1);
1494 symtok = tokeninfo(&val, &st); /* get token read by primary() */
1497 if (matchtoken('[') || matchtoken('{') || matchtoken('('))
1499 tok = tokeninfo(&val, &st); /* get token read by matchtoken() */
1500 if (sym == NULL && symtok != tSYMBOL)
1502 /* we do not have a valid symbol and we appear not to have read a valid
1503 * symbol name (so it is unlikely that we would have read a name of an
1504 * undefined symbol) */
1505 error(29); /* expression error, assumed 0 */
1506 lexpush(); /* analyse '(', '{' or '[' again later */
1509 if (tok == '[' || tok == '{')
1511 close = (char)((tok == '[') ? ']' : '}');
1513 { /* sym==NULL if lval is a constant or a literal */
1514 error(28); /* cannot subscript */
1518 else if (sym->ident != iARRAY && sym->ident != iREFARRAY)
1520 error(28); /* cannot subscript, variable is not an array */
1524 else if (sym->dim.array.level > 0 && close != ']')
1526 error(51); /* invalid subscript, must use [ ] */
1530 stgget(&index, &cidx); /* mark position in code generator */
1531 push1(); /* save base address of the array */
1532 if (hier14(&lval2)) /* create expression for the array index */
1534 if (lval2.ident == iARRAY || lval2.ident == iREFARRAY)
1535 error(33, lval2.sym->name); /* array must be indexed */
1537 if (!matchtag(sym->x.idxtag, lval2.tag, TRUE))
1539 if (lval2.ident == iCONSTEXPR)
1540 { /* constant expression */
1541 stgdel(index, cidx); /* scratch generated code */
1542 if (lval1->arrayidx != NULL)
1543 { /* keep constant index, for checking */
1544 assert(sym->dim.array.level >= 0
1545 && sym->dim.array.level < sDIMEN_MAX);
1546 lval1->arrayidx[sym->dim.array.level] = lval2.constval;
1550 /* normal array index */
1551 if (lval2.constval < 0 || (sym->dim.array.length != 0
1552 && sym->dim.array.length <= lval2.constval))
1553 error(32, sym->name); /* array index out of bounds */
1554 if (lval2.constval != 0)
1556 /* don't add offsets for zero subscripts */
1558 const2(lval2.constval << 1);
1560 const2(lval2.constval << 2);
1567 /* character index */
1568 if (lval2.constval < 0 || (sym->dim.array.length != 0
1569 && sym->dim.array.length * ((8 * sizeof(cell)) /
1571 (ucell) lval2.constval))
1572 error(32, sym->name); /* array index out of bounds */
1573 if (lval2.constval != 0)
1575 /* don't add offsets for zero subscripts */
1577 const2(lval2.constval << 1); /* 16-bit character */
1579 const2(lval2.constval); /* 8-bit character */
1582 charalign(); /* align character index into array */
1587 /* array index is not constant */
1588 lval1->arrayidx = NULL; /* reset, so won't be checked */
1591 if (sym->dim.array.length != 0)
1592 ffbounds(sym->dim.array.length - 1); /* run time check for array bounds */
1593 cell2addr(); /* normal array index */
1597 if (sym->dim.array.length != 0)
1598 ffbounds(sym->dim.array.length * (32 / charbits) - 1);
1599 char2addr(); /* character array index */
1602 ob_add(); /* base address was popped into secondary register */
1604 charalign(); /* align character index into array */
1606 /* the indexed item may be another array (multi-dimensional arrays) */
1607 assert(lval1->sym == sym && sym != NULL); /* should still be set */
1608 if (sym->dim.array.level > 0)
1610 assert(close == ']'); /* checked earlier */
1611 /* read the offset to the subarray and add it to the current address */
1612 lval1->ident = iARRAYCELL;
1613 push1(); /* the optimizer makes this to a MOVE.alt */
1617 /* adjust the "value" structure and find the referenced array */
1618 lval1->ident = iREFARRAY;
1619 lval1->sym = finddepend(sym);
1620 assert(lval1->sym != NULL);
1621 assert(lval1->sym->dim.array.level ==
1622 sym->dim.array.level - 1);
1623 /* try to parse subsequent array indices */
1624 lvalue = FALSE; /* for now, a iREFARRAY is no lvalue */
1627 assert(sym->dim.array.level == 0);
1628 /* set type to fetch... INDIRECTLY */
1629 lval1->ident = (char)((close == ']') ? iARRAYCELL : iARRAYCHAR);
1630 lval1->tag = sym->tag;
1631 /* a cell in an array is an lvalue, a character in an array is not
1632 * always a *valid* lvalue */
1636 { /* tok=='(' -> function(...) */
1638 || (sym->ident != iFUNCTN && sym->ident != iREFFUNC))
1640 if (sym == NULL && sc_status == statFIRST)
1642 /* could be a "use before declaration"; in that case, create a stub
1643 * function so that the usage can be marked.
1645 sym = fetchfunc(lastsymbol, 0);
1647 markusage(sym, uREAD);
1649 return error(12); /* invalid function call */
1651 else if ((sym->usage & uMISSING) != 0)
1653 char symname[2 * sNAMEMAX + 16]; /* allow space for user defined operators */
1655 funcdisplayname(symname, sym->name);
1656 error(4, symname); /* function not defined */
1659 lval1->ident = iEXPRESSION;
1660 lval1->constval = 0;
1661 lval1->tag = sym->tag;
1662 return FALSE; /* result of function call is no lvalue */
1665 if (sym != NULL && lval1->ident == iFUNCTN)
1667 assert(sym->ident == iFUNCTN);
1670 lval1->ident = iREFFUNC;
1671 /* ??? however... function pointers (or function references are not (yet) allowed */
1672 error(29); /* expression error, assumed 0 */
1680 * Returns 1 if the operand is an lvalue (everything except arrays, functions
1681 * constants and -of course- errors).
1682 * Generates code to fetch the address of arrays. Code for constants is
1683 * already generated by constant().
1684 * This routine first clears the entire lval array (all fields are set to 0).
1686 * Global references: intest (may be altered, but restored upon termination)
1689 primary(value * lval)
1696 if (matchtoken('('))
1697 { /* sub-expression - (expression,...) */
1698 pushstk((stkitem) intest);
1699 pushstk((stkitem) sc_allowtags);
1701 intest = 0; /* no longer in "test" expression */
1702 sc_allowtags = TRUE; /* allow tagnames to be used in parenthised expressions */
1704 lvalue = hier14(lval);
1705 while (matchtoken(','));
1707 lexclr(FALSE); /* clear lex() push-back, it should have been
1708 * cleared already by needtoken() */
1709 sc_allowtags = (int)(long)popstk();
1710 intest = (int)(long)popstk();
1714 clear_value(lval); /* clear lval */
1715 tok = lex(&val, &st);
1718 /* lastsymbol is char[sNAMEMAX+1], lex() should have truncated any symbol
1719 * to sNAMEMAX significant characters */
1720 assert(strlen(st) < sizeof lastsymbol);
1721 strcpy(lastsymbol, st);
1723 if (tok == tSYMBOL && !findconst(st))
1725 /* first look for a local variable */
1726 if ((sym = findloc(st)) != 0)
1728 if (sym->ident == iLABEL)
1730 error(29); /* expression error, assumed 0 */
1731 const1(0); /* load 0 */
1732 return FALSE; /* return 0 for labels (expression error) */
1735 lval->ident = sym->ident;
1736 lval->tag = sym->tag;
1737 if (sym->ident == iARRAY || sym->ident == iREFARRAY)
1739 address(sym); /* get starting address in primary register */
1740 return FALSE; /* return 0 for array (not lvalue) */
1744 return TRUE; /* return 1 if lvalue (not label or array) */
1747 /* now try a global variable */
1748 if ((sym = findglb(st)) != 0)
1750 if (sym->ident == iFUNCTN || sym->ident == iREFFUNC)
1752 /* if the function is only in the table because it was inserted as a
1753 * stub in the first pass (i.e. it was "used" but never declared or
1754 * implemented, issue an error
1756 if ((sym->usage & uPROTOTYPED) == 0)
1761 if ((sym->usage & uDEFINE) == 0)
1764 lval->ident = sym->ident;
1765 lval->tag = sym->tag;
1766 if (sym->ident == iARRAY || sym->ident == iREFARRAY)
1768 address(sym); /* get starting address in primary register */
1769 return FALSE; /* return 0 for array (not lvalue) */
1773 return TRUE; /* return 1 if lvalue (not function or array) */
1779 return error(17, st); /* undefined symbol */
1781 assert(sym != NULL);
1782 assert(sym->ident == iFUNCTN || sym->ident != iREFFUNC);
1784 lval->ident = sym->ident;
1785 lval->tag = sym->tag;
1786 return FALSE; /* return 0 for function (not an lvalue) */
1788 lexpush(); /* push the token, it is analyzed by constant() */
1789 if (constant(lval) == 0)
1791 error(29); /* expression error, assumed 0 */
1792 const1(0); /* load 0 */
1794 return FALSE; /* return 0 for constants (or errors) */
1798 clear_value(value * lval)
1801 lval->constval = 0L;
1804 lval->boolresult = FALSE;
1805 /* do not clear lval->arrayidx, it is preset in hier14() */
1809 setdefarray(cell * string, cell size, cell array_sz, cell * dataaddr,
1812 /* The routine must copy the default array data onto the heap, as to avoid
1813 * that a function can change the default value. An optimization is that
1814 * the default array data is "dumped" into the data segment only once (on the
1817 assert(string != NULL);
1819 /* check whether to dump the default array */
1820 assert(dataaddr != NULL);
1821 if (sc_status == statWRITE && *dataaddr < 0)
1825 *dataaddr = (litidx + glb_declared) * sizeof(cell);
1826 for (i = 0; i < size; i++)
1830 /* if the function is known not to modify the array (meaning that it also
1831 * does not modify the default value), directly pass the address of the
1832 * array in the data segment.
1840 /* Generate the code:
1841 * CONST.pri dataaddr ;address of the default array data
1842 * HEAP array_sz*sizeof(cell) ;heap address in ALT
1843 * MOVS size*sizeof(cell) ;copy data from PRI to ALT
1844 * MOVE.PRI ;PRI = address on the heap
1847 /* "array_sz" is the size of the argument (the value between the brackets
1848 * in the declaration), "size" is the size of the default array data.
1850 assert(array_sz >= size);
1851 modheap((int)array_sz * sizeof(cell));
1852 /* ??? should perhaps fill with zeros first */
1853 memcopy(size * sizeof(cell));
1859 findnamedarg(arginfo * arg, char *name)
1863 for (i = 0; arg[i].ident != 0 && arg[i].ident != iVARARGS; i++)
1864 if (strcmp(arg[i].name, name) == 0)
1870 checktag(int tags[], int numtags, int exprtag)
1875 assert(numtags > 0);
1876 for (i = 0; i < numtags; i++)
1877 if (matchtag(tags[i], exprtag, TRUE))
1878 return TRUE; /* matching tag */
1879 return FALSE; /* no tag matched */
1891 * Generates code to call a function. This routine handles default arguments
1892 * and positional as well as named parameters.
1895 callfunction(symbol * sym)
1898 int argpos; /* index in the output stream (argpos==nargs if positional parameters) */
1899 int argidx = 0; /* index in "arginfo" list */
1900 int nargs = 0; /* number of arguments */
1902 int namedparams = FALSE;
1903 value lval = { NULL, 0, 0, 0, 0, NULL };
1905 char arglist[sMAXARGS];
1906 constvalue arrayszlst = { NULL, "", 0, 0 }; /* array size list starts empty */
1910 assert(sym != NULL);
1911 arg = sym->dim.arglist;
1912 assert(arg != NULL);
1913 stgmark(sSTARTREORDER);
1914 for (argpos = 0; argpos < sMAXARGS; argpos++)
1915 arglist[argpos] = ARG_UNHANDLED;
1916 if (!matchtoken(')'))
1920 if (matchtoken('.'))
1923 if (needtoken(tSYMBOL))
1924 tokeninfo(&lexval, &lexstr);
1927 argpos = findnamedarg(arg, lexstr);
1930 error(17, lexstr); /* undefined symbol */
1931 break; /* exit loop, argpos is invalid */
1939 error(44); /* positional parameters must precede named parameters */
1942 stgmark((char)(sEXPRSTART + argpos)); /* mark beginning of new expression in stage */
1943 if (arglist[argpos] != ARG_UNHANDLED)
1944 error(58); /* argument already set */
1945 if (matchtoken('_'))
1947 arglist[argpos] = ARG_IGNORED; /* flag argument as "present, but ignored" */
1948 if (arg[argidx].ident == 0 || arg[argidx].ident == iVARARGS)
1950 error(202); /* argument count mismatch */
1952 else if (!arg[argidx].hasdefault)
1954 error(34, nargs + 1); /* argument has no default value */
1956 if (arg[argidx].ident != 0 && arg[argidx].ident != iVARARGS)
1958 /* The rest of the code to handle default values is at the bottom
1959 * of this routine where default values for unspecified parameters
1960 * are (also) handled. Note that above, the argument is flagged as
1966 arglist[argpos] = ARG_DONE; /* flag argument as "present" */
1967 lvalue = hier14(&lval);
1968 switch (arg[argidx].ident)
1971 error(202); /* argument count mismatch */
1974 /* always pass by reference */
1975 if (lval.ident == iVARIABLE || lval.ident == iREFERENCE)
1977 assert(lval.sym != NULL);
1978 if ((lval.sym->usage & uCONST) != 0
1979 && (arg[argidx].usage & uCONST) == 0)
1981 /* treat a "const" variable passed to a function with a non-const
1982 * "variable argument list" as a constant here */
1984 rvalue(&lval); /* get value in PRI */
1985 setheap_pri(); /* address of the value on the heap in PRI */
1994 setheap_pri(); /* address of the value on the heap in PRI */
1998 else if (lval.ident == iCONSTEXPR
1999 || lval.ident == iEXPRESSION
2000 || lval.ident == iARRAYCHAR)
2002 /* fetch value if needed */
2003 if (lval.ident == iARRAYCHAR)
2005 /* allocate a cell on the heap and store the
2006 * value (already in PRI) there */
2007 setheap_pri(); /* address of the value on the heap in PRI */
2010 /* ??? handle const array passed by reference */
2011 /* otherwise, the address is already in PRI */
2012 if (lval.sym != NULL)
2013 markusage(lval.sym, uWRITTEN);
2015 * Dont need this warning - its varargs. there is no way of knowing the
2016 * required tag/type...
2018 if (!checktag(arg[argidx].tags,arg[argidx].numtags,lval.tag))
2023 if (lval.ident == iLABEL || lval.ident == iFUNCTN
2024 || lval.ident == iREFFUNC || lval.ident == iARRAY
2025 || lval.ident == iREFARRAY)
2026 error(35, argidx + 1); /* argument type mismatch */
2028 rvalue(&lval); /* get value (direct or indirect) */
2029 /* otherwise, the expression result is already in PRI */
2030 assert(arg[argidx].numtags > 0);
2031 check_userop(NULL, lval.tag, arg[argidx].tags[0], 2,
2034 (arg[argidx].tags, arg[argidx].numtags, lval.tag))
2036 argidx++; /* argument done */
2039 if (!lvalue || lval.ident == iARRAYCHAR)
2040 error(35, argidx + 1); /* argument type mismatch */
2041 if (lval.sym != NULL && (lval.sym->usage & uCONST) != 0
2042 && (arg[argidx].usage & uCONST) == 0)
2043 error(35, argidx + 1); /* argument type mismatch */
2044 if (lval.ident == iVARIABLE || lval.ident == iREFERENCE)
2048 assert(lval.sym != NULL);
2053 setheap_pri(); /* address of the value on the heap in PRI */
2057 /* otherwise, the address is already in PRI */
2059 (arg[argidx].tags, arg[argidx].numtags, lval.tag))
2061 argidx++; /* argument done */
2062 if (lval.sym != NULL)
2063 markusage(lval.sym, uWRITTEN);
2066 if (lval.ident != iARRAY && lval.ident != iREFARRAY
2067 && lval.ident != iARRAYCELL)
2069 error(35, argidx + 1); /* argument type mismatch */
2072 if (lval.sym != NULL && (lval.sym->usage & uCONST) != 0
2073 && (arg[argidx].usage & uCONST) == 0)
2074 error(35, argidx + 1); /* argument type mismatch */
2075 /* Verify that the dimensions match with those in arg[argidx].
2076 * A literal array always has a single dimension.
2077 * An iARRAYCELL parameter is also assumed to have a single dimension.
2079 if (lval.sym == NULL || lval.ident == iARRAYCELL)
2081 if (arg[argidx].numdim != 1)
2083 error(48); /* array dimensions must match */
2085 else if (arg[argidx].dim[0] != 0)
2087 assert(arg[argidx].dim[0] > 0);
2088 if (lval.ident == iARRAYCELL)
2090 error(47); /* array sizes must match */
2094 assert(lval.constval != 0); /* literal array must have a size */
2095 /* A literal array must have exactly the same size as the
2096 * function argument; a literal string may be smaller than
2097 * the function argument.
2099 if ((lval.constval > 0
2100 && arg[argidx].dim[0] != lval.constval)
2101 || (lval.constval < 0
2102 && arg[argidx].dim[0] <
2104 error(47); /* array sizes must match */
2107 if (lval.ident != iARRAYCELL)
2109 /* save array size, for default values with uSIZEOF flag */
2110 cell array_sz = lval.constval;
2112 assert(array_sz != 0); /* literal array must have a size */
2114 array_sz = -array_sz;
2115 append_constval(&arrayszlst, arg[argidx].name,
2121 symbol *sym = lval.sym;
2124 assert(sym != NULL);
2125 if (sym->dim.array.level + 1 != arg[argidx].numdim)
2126 error(48); /* array dimensions must match */
2127 /* the lengths for all dimensions must match, unless the dimension
2128 * length was defined at zero (which means "undefined")
2130 while (sym->dim.array.level > 0)
2132 assert(level < sDIMEN_MAX);
2133 if (arg[argidx].dim[level] != 0
2134 && sym->dim.array.length !=
2135 arg[argidx].dim[level])
2136 error(47); /* array sizes must match */
2137 append_constval(&arrayszlst, arg[argidx].name,
2138 sym->dim.array.length, level);
2139 sym = finddepend(sym);
2140 assert(sym != NULL);
2143 /* the last dimension is checked too, again, unless it is zero */
2144 assert(level < sDIMEN_MAX);
2145 assert(sym != NULL);
2146 if (arg[argidx].dim[level] != 0
2147 && sym->dim.array.length !=
2148 arg[argidx].dim[level])
2149 error(47); /* array sizes must match */
2150 append_constval(&arrayszlst, arg[argidx].name,
2151 sym->dim.array.length, level);
2153 /* address already in PRI */
2155 (arg[argidx].tags, arg[argidx].numtags, lval.tag))
2157 // ??? set uWRITTEN?
2158 argidx++; /* argument done */
2161 push1(); /* store the function argument on the stack */
2162 endexpr(FALSE); /* mark the end of a sub-expression */
2164 assert(arglist[argpos] != ARG_UNHANDLED);
2166 close = matchtoken(')');
2167 if (!close) /* if not paranthese... */
2168 if (!needtoken(',')) /* ...should be comma... */
2169 break; /* ...but abort loop if neither */
2171 while (!close && freading && !matchtoken(tENDEXPR)); /* do */
2173 /* check remaining function arguments (they may have default values) */
2174 for (argidx = 0; arg[argidx].ident != 0 && arg[argidx].ident != iVARARGS;
2177 if (arglist[argidx] == ARG_DONE)
2178 continue; /* already seen and handled this argument */
2179 /* in this first stage, we also skip the arguments with uSIZEOF and uTAGOF;
2180 * these are handled last
2182 if ((arg[argidx].hasdefault & uSIZEOF) != 0
2183 || (arg[argidx].hasdefault & uTAGOF) != 0)
2185 assert(arg[argidx].ident == iVARIABLE);
2188 stgmark((char)(sEXPRSTART + argidx)); /* mark beginning of new expression in stage */
2189 if (arg[argidx].hasdefault)
2191 if (arg[argidx].ident == iREFARRAY)
2195 setdefarray(arg[argidx].defvalue.array.data,
2196 arg[argidx].defvalue.array.size,
2197 arg[argidx].defvalue.array.arraysize,
2198 &arg[argidx].defvalue.array.addr,
2199 (arg[argidx].usage & uCONST) != 0);
2200 if ((arg[argidx].usage & uCONST) == 0)
2201 heapalloc += arg[argidx].defvalue.array.arraysize;
2202 /* keep the lengths of all dimensions of a multi-dimensional default array */
2203 assert(arg[argidx].numdim > 0);
2204 if (arg[argidx].numdim == 1)
2206 append_constval(&arrayszlst, arg[argidx].name,
2207 arg[argidx].defvalue.array.arraysize, 0);
2211 for (level = 0; level < arg[argidx].numdim; level++)
2213 assert(level < sDIMEN_MAX);
2214 append_constval(&arrayszlst, arg[argidx].name,
2215 arg[argidx].dim[level], level);
2219 else if (arg[argidx].ident == iREFERENCE)
2221 setheap(arg[argidx].defvalue.val);
2222 /* address of the value on the heap in PRI */
2227 int dummytag = arg[argidx].tags[0];
2229 const1(arg[argidx].defvalue.val);
2230 assert(arg[argidx].numtags > 0);
2231 check_userop(NULL, arg[argidx].defvalue_tag,
2232 arg[argidx].tags[0], 2, NULL, &dummytag);
2233 assert(dummytag == arg[argidx].tags[0]);
2235 push1(); /* store the function argument on the stack */
2236 endexpr(FALSE); /* mark the end of a sub-expression */
2240 error(202, argidx); /* argument count mismatch */
2242 if (arglist[argidx] == ARG_UNHANDLED)
2244 arglist[argidx] = ARG_DONE;
2246 /* now a second loop to catch the arguments with default values that are
2247 * the "sizeof" or "tagof" of other arguments
2249 for (argidx = 0; arg[argidx].ident != 0 && arg[argidx].ident != iVARARGS;
2255 if (arglist[argidx] == ARG_DONE)
2256 continue; /* already seen and handled this argument */
2257 stgmark((char)(sEXPRSTART + argidx)); /* mark beginning of new expression in stage */
2258 assert(arg[argidx].ident == iVARIABLE); /* if "sizeof", must be single cell */
2259 /* if unseen, must be "sizeof" or "tagof" */
2260 assert((arg[argidx].hasdefault & uSIZEOF) != 0
2261 || (arg[argidx].hasdefault & uTAGOF) != 0);
2262 if ((arg[argidx].hasdefault & uSIZEOF) != 0)
2264 /* find the argument; if it isn't found, the argument's default value
2265 * was a "sizeof" of a non-array (a warning for this was already given
2266 * when declaring the function)
2268 asz = find_constval(&arrayszlst, arg[argidx].defvalue.size.symname,
2269 arg[argidx].defvalue.size.level);
2272 array_sz = asz->value;
2274 error(224, arg[argidx].name); /* indeterminate array size in "sizeof" expression */
2285 assert((arg[argidx].hasdefault & uTAGOF) != 0);
2286 sym = findloc(arg[argidx].defvalue.size.symname);
2288 sym = findglb(arg[argidx].defvalue.size.symname);
2289 array_sz = (sym != NULL) ? sym->tag : 0;
2290 exporttag(array_sz);
2293 push1(); /* store the function argument on the stack */
2295 if (arglist[argidx] == ARG_UNHANDLED)
2297 arglist[argidx] = ARG_DONE;
2299 stgmark(sENDREORDER); /* mark end of reversed evaluation */
2300 pushval((cell) nargs * sizeof(cell));
2302 if (sc_status != statSKIP)
2303 markusage(sym, uREAD); /* do not mark as "used" when this call itself is skipped */
2304 if (sym->x.lib != NULL)
2305 sym->x.lib->value += 1; /* increment "usage count" of the library */
2306 modheap(-heapalloc * sizeof(cell));
2307 sideeffect = TRUE; /* assume functions carry out a side-effect */
2308 delete_consttable(&arrayszlst); /* clear list of array sizes */
2313 * Returns a non-zero value if lval1 an array and lval2 is not an array and
2314 * the operation is addition or subtraction.
2316 * Returns the "shift" count (1 for 16-bit, 2 for 32-bit) to align a cell
2317 * to an array offset.
2320 dbltest(void (*oper) (), value * lval1, value * lval2)
2322 if ((oper != ob_add) && (oper != ob_sub))
2324 if (lval1->ident != iARRAY)
2326 if (lval2->ident == iARRAY)
2328 return sizeof(cell) / 2; /* 1 for 16-bit, 2 for 32-bit */
2333 * Test whether an operator is commutative, i.e. x oper y == y oper x.
2334 * Commutative operators are: + (addition)
2335 * * (multiplication)
2342 * If in an expression, code for the left operand has been generated and
2343 * the right operand is a constant and the operator is commutative, the
2344 * precautionary "push" of the primary register is scrapped and the constant
2345 * is read into the secondary register immediately.
2348 commutative(void (*oper) ())
2350 return oper == ob_add || oper == os_mult
2351 || oper == ob_eq || oper == ob_ne
2352 || oper == ob_and || oper == ob_xor || oper == ob_or;
2357 * Generates code to fetch a number, a literal character (which is returned
2358 * by lex() as a number as well) or a literal string (lex() stores the
2359 * strings in the literal queue). If the operand was a number, it is stored
2360 * in lval->constval.
2362 * The function returns 1 if the token was a constant or a string, 0
2366 constant(value * lval)
2368 int tok, index, constant;
2369 cell val, item, cidx;
2373 tok = lex(&val, &st);
2374 if (tok == tSYMBOL && (sym = findconst(st)) != 0)
2376 lval->constval = sym->addr;
2377 const1(lval->constval);
2378 lval->ident = iCONSTEXPR;
2379 lval->tag = sym->tag;
2380 markusage(sym, uREAD);
2382 else if (tok == tNUMBER)
2384 lval->constval = val;
2385 const1(lval->constval);
2386 lval->ident = iCONSTEXPR;
2388 else if (tok == tRATIONAL)
2390 lval->constval = val;
2391 const1(lval->constval);
2392 lval->ident = iCONSTEXPR;
2393 lval->tag = sc_rationaltag;
2395 else if (tok == tSTRING)
2397 /* lex() stores starting index of string in the literal table in 'val' */
2398 const1((val + glb_declared) * sizeof(cell));
2399 lval->ident = iARRAY; /* pretend this is a global array */
2400 lval->constval = val - litidx; /* constval == the negative value of the
2401 * size of the literal array; using a negative
2402 * value distinguishes between literal arrays
2403 * and literal strings (this was done for
2404 * array assignment). */
2406 else if (tok == '{')
2408 int tag, lasttag = -1;
2413 /* cannot call constexpr() here, because "staging" is already turned
2414 * on at this point */
2416 stgget(&index, &cidx); /* mark position in code generator */
2417 expression(&constant, &item, &tag, FALSE);
2418 stgdel(index, cidx); /* scratch generated code */
2420 error(8); /* must be constant expression */
2423 else if (!matchtag(lasttag, tag, FALSE))
2424 error(213); /* tagname mismatch */
2425 stowlit(item); /* store expression result in literal table */
2427 while (matchtoken(','));
2429 const1((val + glb_declared) * sizeof(cell));
2430 lval->ident = iARRAY; /* pretend this is a global array */
2431 lval->constval = litidx - val; /* constval == the size of the literal array */
2435 return FALSE; /* no, it cannot be interpreted as a constant */
2437 return TRUE; /* yes, it was a constant value */